/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | foam-extend: Open Source CFD
   \\    /   O peration     | Version:     4.1
    \\  /    A nd           | Web:         http://www.foam-extend.org
     \\/     M anipulation  | For copyright notice see file Copyright
-------------------------------------------------------------------------------
License
	This file is part of foam-extend.

	foam-extend is free software: you can redistribute it and/or modify it
	under the terms of the GNU General Public License as published by the
	Free Software Foundation, either version 3 of the License, or (at your
	option) any later version.

	foam-extend is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with foam-extend.  If not, see <http://www.gnu.org/licenses/>.

Description
	Read of a non-delimited hex label

\*---------------------------------------------------------------------------*/

#include "readHexLabel.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

Foam::label Foam::readHexLabel(ISstream& is)
{
	// Takes into account that 'a' (or 'A') is 10
	static const label alphaOffset = toupper('A') - 10;
	// Takes into account that '0' is 0
	static const label zeroOffset = int('0');

	char c = 0;

	// Get next non-whitespace character
	while (is.get(c) && isspace(c))
	{}

	label result = 0;
	do
	{
		if (isspace(c) || c == 0) break;

		if (!isxdigit(c))
		{
			FatalIOErrorIn("readHexLabel(ISstream&)", is)
				<< "Illegal hex digit: '" << c << "'"
				<< exit(FatalIOError);
		}

		result *= 16;

		if (isdigit(c))
		{
			result += int(c) - zeroOffset;
		}
		else
		{
			result += toupper(c) - alphaOffset;
		}
	} while (is.get(c));

	return result;
}


// ************************************************************************* //
